1. Field of the Invention
The invention is related to the field of communications, and in particular, to methods and computer readable mediums for determining processor occupancy (PO) and capacity of home location register (HLR) nodes of an HLR cluster.
2. Statement of the Problem
A large capacity mobile switching center (MSC) in a wireless communication network may include millions of subscriber profile records managed by an HLR and/or a visitor location register (VLR) system. The management functionality of an HLR includes retrieving a subscriber profile record responsive to a call, autonomous registration, or another event, and providing the MSC (or other network elements) with the content of the subscriber profile record. The HLR is also responsible for updating a subscriber profile record if changes are necessary as a result of an event (such as a call, location change, etc.)
Because of the large number of subscriber profile records managed by an HLR, one HLR application processor often can't handle the workload for an MSC. Thus, a cluster of HLR nodes is often utilized, with the load of requests from the MSC balanced across the cluster of HLR nodes. In this type of configuration, the HLR nodes of the cluster should maintain a consistent profile database, because any of the nodes could be responsible for processing a request for a subscriber profile record at any particular time. Therefore, an updated record (including insertion of a new record or deletion of an existing record) on one node should be replicated to the peer nodes in the cluster in order to maintain a consistent profile for each subscriber of the wireless communication network.
As the workload of an MSC increases, more HLR nodes are added to the HLR cluster. As a result, the update and replication processing for the subscriber profile records across the HLR nodes is increased significantly, especially when a profile update is required for every call, autonomous registration, or other event. This update and replication process diminishes the capacity of each HLR node, because a significant amount of processing time is expended transmitting messages between the HLR nodes to update profile records and updating the database on each HLR node. Therefore, there is not a straight linear relationship between the number of HLR nodes in an HLR cluster and the capacity of the HLR cluster. Thus, it is a problem for network operators to determine the processor occupancy of a cluster of HLR nodes, and the number of HLR nodes needed to handle the workload of the MSC.